Abstract
This paper gives a classification of the control action of a man in a manual control system furnished with CRT display and hand-driven controllers, performing compensatory tracking to step input. Two types of controllers, i.e. the continuous controller of non-homing type and the three states switch controller (-1, 0, 1) are compared.
The control action to a step input can be divided into three processes, the initial process, the control process and the stabilizing process.
The initial process, beginning from the onset of input and lasting till the initiation of correct control movement to the input, is a certain latent period and occassionally includes a fault initial controller movement.
The control process begins at the initiation of correct control movement and lasts until the most part of the error imposed by the step input is compensated.
After the compensation of the error starts the stabilization process, which is due to keep the error in the desired level stably.
The control mode of a man in the control and stabilizing processes changes with the order and type of the plant to be controlled and with the controller.
In the control process, two types of control modes are observed. The one, named the linear mode (L), is observed for the plants of the lower order (1st & 2nd). For the higher order plants (2nd & 3rd), the bang-bang mode (BB) is dominant.
In the stabilizing process, four modes are observed. Firstly, the damped bang-bang mode (DB), secondly the steady state bang-bang mode (SB), thirdly, the bang-zero mode (B0) and lastly, the spike mode (SP).
The DB mode is found when the continuous controller is used. The SB mode is observed with the both types of controllers. The B0 mode is found when a 0-type plant is controlled by the 3 states switch. The spike mode is observed only when the 3 states switch is used.
The DB and SP modes are dominant in the trained subjects, while the less trained subjects are apt to use the SB or B0 mode in the stabilizing process.
